What is the history of Persia?

Persia began as a client state of the Medes. It took over Media and used the combined strength to take over the Babylonian Empire and Assyria, then extending to the remainder of the Middle East, Egypyt and Libya, Thrace and Macedonia, and Central Asia.

In taking over Asia Minor it brought under its control a large number of Greek city-states. These were restive, and when they revolted in 499 BCE, their mother cities Eretria and Athens in mainland Greece supported them militarily. When the revolt had been quashed, Persia decided to instal tyrants in those two cities, tut its enforcement expedition was defeated at Marathon. The Persians then decided that the only way to avoid ongoing disruption in their empire was to bring all the Greek city-states under control of a Persian governor. Some cities agreed, and an invasion force was launched to coerce the rest. This failed in 480-470 BCE, and follow-up war continued until the Persians agreed to stay away from the Greek cities in 449 BCE, and Persia went back to promoting peace and prosperity within its basic empire.

This left the Greeks to go back to fighting increasingly devastating wars amongst each other, and in the 390s the Persian king demanded that this cease or he would impose peace by force on the no weakened cities. This stand-off continued until Alexander the Great launched a campaign which took over the Persian Empire which came under Macedonian control and was split into several separate Macedonian kingdoms after Alexander's death.